Dyadic efficacy for smoking cessation: preliminary assessment of a new instrument

Smoking cessation research has demonstrated a link between social support and quitting, but interventions designed to enhance partner support have often failed. We adapted and tested a measure of dyadic efficacy to assess smokers' confidence in their abilities to work together as a team with their partners to quit smoking and cope with quitting challenges. Our goal was to establish the psychometric properties of the dyadic efficacy instrument, including its associations with cessation outcomes.

We recruited partnered smokers who called the American Cancer Society's Quitline and administered telephone interviews (N = 634, 59% female, average age = 40 years). Interviews included 8 dyadic efficacy items and a variety of sociodemographic, smoking history, and relationship variables at baseline and quit outcomes at 4 months.

Factor analysis of the dyadic efficacy items yielded a 1-factor scale with strong internal consistency (α = .92). Dyadic efficacy was positively associated (p < .0001) with smoking-specific support (r = .51), relationship satisfaction (r = .44), and dyadic coping (r = .54). Dyadic efficacy was not associated with age, gender, race, relationship length, smoking quantity, or previous quit attempts. Respondents with smoking partners who were willing to quit with them had higher dyadic efficacy than those whose smoking partners were not (p < .0001). Higher baseline dyadic efficacy was predictive of 7-day point prevalence quit rates at follow-up (odds ratio = 1.25, 95% CI = 1.02-1.53).

With further study, dyadic efficacy may enhance our understanding of the role of partner relationships in smoking cessation.